A study in this month's issue of the American Journal of Gastroenterology compares the rate of gastrointestinal bleeding in patients taking non-vitamin K antagonist oral anticoagulants or warfarin.

Early reports suggested that the risk of gastrointestinal bleeding was higher for patients on non-vitamin K antagonist oral anticoagulants than for those on warfarin.

Dr Linda Feagins and colleagues from Texas, USA compared the incidence of gastrointestinal bleeding in their patients on non-vitamin K antagonist oral anticoagulants with those on warfarin.

The researchers used their VA pharmacy database to identify patients taking non-vitamin K antagonist oral anticoagulants or warfarin between 2011 and 2015, and used the VistA system to identify those who were hospitalized for gastrointestinal bleeding.

The team included only patients with clinically significant gastrointestinal bleeding, defined as documented gastrointestinal blood loss with a hemoglobin drop ≥2 g/dl, hemodynamic instability, and/or need for endoscopic evaluation, angiography, or surgery.

8% of patients in the warfarin group died

American Journal of Gastroenterology

The research team identified 803 patients on non-vitamin K antagonist oral anticoagulants, and 6,263 on warfarin.

The team found that 3% of patients on warfarin had gastrointestinal bleeding, compared with less than 1% of patients on non-vitamin K antagonist oral anticoagulants.

The researchers observed that blood transfusion for gastrointestinal bleeding was significantly more common in patients on warfarin than on non-vitamin K antagonist oral anticoagulants.

Within 90 days of gastrointestinal bleeding hospitalization, 8% of patients in the warfarin group died, whereas there were no deaths in the non-vitamin K antagonist oral anticoagulant group.

Dr Feagins' team comments, "In our patients, the incidence of gastrointestinal bleeding for those on warfarin was more than 4 times that for those on non-vitamin K antagonist oral anticoagulants."

"Blood transfusions for gastrointestinal bleeding were more common in warfarin patients, and no non-vitamin K antagonist oral anticoagulants patients died of gastrointestinal bleeding."

"In contrast to early reports, our findings suggest that the risk of gastrointestinal bleeding, and subsequent complications is considerably lower for patients on non-vitamin K antagonist oral anticoagulants than for patients on warfarin."